UniqueExpireCache.h

//// UniqueExpireCache.h//// $Id: //poco/1.3/Foundation/include/Poco/UniqueExpireCache.h#1 $//// Library: Foundation// Package: Cache// Module: UniqueExpireCache//// Definition of the UniqueExpireCache class.//// Copyright (c) 2006, Applied Informatics Software Engineering GmbH.// and Contributors.//// Permission is hereby granted, free of charge, to any person or organization// obtaining a copy of the software and accompanying documentation covered by// this license (the "Software") to use, reproduce, display, distribute,// execute, and transmit the Software, and to prepare derivative works of the// Software, and to permit third-parties to whom the Software is furnished to// do so, all subject to the following:// // The copyright notices in the Software and this entire statement, including// the above license grant, this restriction and the following disclaimer,// must be included in all copies of the Software, in whole or in part, and// all derivative works of the Software, unless such copies or derivative// works are solely in the form of machine-executable object code generated by// a source language processor.// // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER// DEALINGS IN THE SOFTWARE.//#ifndef Foundation_UniqueExpireCache_INCLUDED#define Foundation_UniqueExpireCache_INCLUDED#include "Poco/AbstractCache.h"#include "Poco/UniqueExpireStrategy.h"namespace Poco {
template <class TKey, class TValue>
00051class UniqueExpireCache: publicAbstractCache<TKey, TValue, UniqueExpireStrategy<TKey, TValue> > /// An UniqueExpireCache caches entries for a given time amount. In contrast /// to ExpireCache which only allows to set a per cache expiration value, it allows to define /// expiration per CacheEntry. /// Each TValue object must thus offer the following method: /// /// const Poco::Timestamp& getExpiration() const; /// /// which returns the absolute timepoint when the entry will be invalidated. /// /// Be careful when using an UniqueExpireCache. A cache is often used /// like cache.has(x) followed by cache.get x). Note that it could happen /// that the "has" call works, then the current execution thread gets descheduled, time passes, /// the entry gets invalid, thus leading to an empty SharedPtr being returned /// when "get" is invoked.{
public:
UniqueExpireCache():
AbstractCache<TKey, TValue, UniqueExpireStrategy<TKey, TValue> >(UniqueExpireStrategy<TKey, TValue>())
{
}
~UniqueExpireCache()
{
}
private:
UniqueExpireCache(constUniqueExpireCache& aCache);
UniqueExpireCache& operator = (constUniqueExpireCache& aCache);
};
} // namespace Poco#endif